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Amerisleep AS4 vs Helix Midnight

Easily compare the Helix Midnight vs Amerisleep AS4 Mattresses side-by-side.

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Essential Mattress Info

Brand
AmerisleepHelix (USA)
Mattress Type
Memory foamHybrid (coils and foam)
Prices
Video

Trial & Warranty

Trial Period
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Trial Period (nights)
100100
Warranty Length (years)
2010

Firmness Options

One Firmness Fits All?
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Adjustable Firmness
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Half-Half Firmness
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Selectable Firmness
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Flippable / Reversible Firmness
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Firmness Info

The AS4 is our medium-soft mattress. It offers plush comfort with targeted support that helps you sleep your best. Plus it stays cool all night, making it our most popular model with side sleepers.

Medium feel top of the bed you need - not too firm, not too soft. Our most common feel choice. Balanced support - best for side sleepers with thin to average body types. A 4-7 on the firmness scale.

Mattress Construction

Materials Overview

Three layer construction:

  • Bio-Pur® foam
  • HIVE® transition layer
  • Bio-Core® foam support layer
  • Refresh Cooling Cover.

The Midnight offers balanced support and a medium feel, it has four layers of construction:

  • Cover: Helix Two Touch Design
  • Comfort Layer: Memory Plus Foam (Density: 2.5 PCF)
  • Transition Layer: High-Grade Polyfoam
  • Body Shape Layer: 6" Wrapped Coils
  • Base Layer: DuraDense Foam.

Comfort Info

Traditional memory foam is made from dense material, so it traps your body heat and can make you sweaty and uncomfortable while you're in bed - and who can sleep like that?
We developed our foam with an enhanced "open cell structure", which means there is more air space between the foam particles. That space wicks away heat while you sleep, and can keep you cooler and more comfortable.

Support Info

Our Bio-Core® foam support layer won't sag even after decades of use. And, like our Bio-Pur® foam, it's partially made from plants instead of petroleum so it's eco-friendly.
The HIVE® layer features hundreds of foam hexagons grouped into five comfort zones. Each zone is designed to provide extra cushion where you want it and support where you need it. That way your body gets the support it needs to stay properly aligned, so you can sleep your best.

Specially designed using a Memory Plus Foam pressure relief layer to cushion your pressure points as a side sleeper.
Density of the top and middle layers optimized to give you the right amount of support based on your body type.

Comfort Specs

The HIVE® transition layer has precision-cut channels that carry away even more heat and moisture. It's enough to make you feel like you're weightlessly resting on a cloud.
Amerisleep's Bio-Pur® material features an advanced-open cell design. This makes Bio-Pur® more breathable and responsive than memory foam, which will keep you cool and comfortable all night. Plus we make Bio-Pur® from partially plant-based sources using a zero-emission process. That means it's the most eco-friendly material of its kind.

Uniquely pressure relieving, we use Memory Plus Foam - a special Helix blend.

Support Specs

Bio-Pur® contours to your body to relieve pressure points and bounces back fast, so you won't feel "stuck" during the night.
Our HIVE® transition layer provides targeted support and pressure relief so you can sleep in perfect alignment. It gives your head, back, and legs more support, and your shoulders and hips more cushion.

High-Grade Polyfoam
Providing ergonomic support and cushioning, the transition layer has a medium IFD to match your body type.
Wrapped Coils
Hundreds of individual coils help to cradle your body while also limiting motion transfer.
Edge Support
Each mattress has an individually wrapped spring unit with a reinforced perimeter. This means your mattress will reduce that roll-off feeling and will keep its shape more while sitting on the edge of the bed. Our technology is proven to be substantially better than all foam options.

Fabric Specs

Refresh Cooling Cover
The Refresh Cover draws heat from your skin for a delightfully cool-to-the-touch feel. On average, your sleeping surface will stay 7 degrees cooler over an eight-hour night of rest compared to a traditional 100% polyester cover. This scientifically engineered fabric uses minerals to help convert your natural body heat into far infrared energy. This type of energy increases blood circulation to help speed up muscle recovery and improve quality of sleep.

Helix Two Touch Design
Each mattress comes with a top cover layer with stretch and a soft touch as well as a lower cover layer for airflow and breathability. Top cover - 100% soft polyester. Lower cover - Jersey knit fabric with woven fire barrier.
Upgrade to ultra cool knit cover for cooler nights (available at checkout). This Ultra-Cool Cover is designed using phase change material to keep your body cool when you sleep. Simply zip on the Ultra-Cool Cover in place of your standard cover for quick and easy use.

Manufactured in
United StatesUnited States

Suitability

Side Sleepers
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Back Sleepers
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Size & Weight

Twin
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Twin Dimensions
74 x 38 x 12 "75 x 39 x 11.5 "
Twin Weight (lb)
56
Twin XL
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Twin XL Dimensions
80 x 38 x 12 "80 x 39 x 11.5 "
Twin XL Weight (lb)
62
Full
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Full Dimensions
75 x 54 x 12 "75 x 54 x 11.5 "
Full Weight (lb)
79
Queen
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Queen Dimensions
80 x 60 x 12 "80 x 60 x 11.5 "
Queen Weight (lb)
92
King
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King Dimensions
80 x 76 x 12 "80 x 76 x 11.5 "
King Weight (lb)
117
Cal King
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Cal King Dimensions
84 x 72 x 12 "84 x 72 x 11.5 "
Cal King Weight (lb)
117

Certifications & Sustainability

Certifications
CertiPur-US®
CertiPur-US®
CertiPur-US®
GREENGUARD Gold
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GREENGUARD Gold
Other Certification Info

Delivery

Delivery Cost
FREEYES
Delivery Info

We provide standard free curbside shipping to anywhere in the contiguous USA. Mattresses ship as quickly as 3-5 working days (excluding major holidays) via FedEx, once shipped, delivery takes approximately 1-5 business days.

Your Helix Mattress is gently compressed, rolled, and put in a box that's about the size of a bag of golf clubs for easy shipping! Packaging dimensions are 16" x 16" x 48", and we ship via UPS Ground direct from the manufacture to your door.

Prices
Latest Promotions
Ends Sunday $450 OFF any mattress. Free, no contact delivery & free returns ! Promo : AS450.
See offer
Find the Perfect Mattress for How You Sleep
Which mattress is right ?
🎁 March Madness Sale ! 20% Off sitewide + 2 FREE Dream Pillows with Mattress Purchase ($150+ Value) Use Code: MADNESS20
See offer